NEW BOOKS Raumchemie der festen Stoffe. By W. BILTZ. 24 x 16 cm. x 4- 338 pp. Leipzic: Leopold Voss, 1934. Price: unbound, 22.5 RM; bound, 24 RM. The present volume has been produced by Professor Bilts and a number of collaborators, and is a very illuminating account of the information which may be gained from a study of molecular volumes of large numbers of substances. The approach t o the subject is perhaps somewhat old-fashioned in the sense that tabular information concerning atomic and ionic radii as determined by crystal analysis has not been given, although references t o crystallographic literature are very full and up-to-date. The first part of the book gives tabular information on molecular volumes and densities of solids corrected back t o absolute zero, and the references t o original work set out in detail at the end of each table number several hundred. Although the writers in most instances refer t o the type of crystal structure of a particular compound and to the determination of its atomic arrangement, this is as far as the author goes in presenting the more modern physical results. The book is of a distinctly different type than Hassel’s recent Krystalkhemie and covers a much greater range of substances in a more general way. The considerations of radius-ratio and the additive laws for atomic volumes and atomic radii do not perhaps receive quite so much attention as some readers may wish. The book seems to fall between the entirely tabular type and that of a treatise, with the consequence that the lack of a substance index of any kind makes i t a little difficult t o use as a detailed work of reference. There is no question, however, t h a t i t is an extremely valuable compilation, and the excellent diagrams summarize the more important conclusions arrived at. The end-cover contains a detachable sheet of atomic and ionic volumes set out in the form of the periodic table; this should prove very valuable for quick reference. J. T. RANDALL.
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Thermionic Emission. By A. L. REIMANN.23 x 15 cm.; xi 324 pp. London: Chapman and Hall, 1934. Price: 21s. The subject of thermionics is one which has attracted a good deal of interest during the last thirty years, but it is only very recently that a more complete understanding of the mechanism of electron emission by heated bodies has come about. The application of modern quantum statistics t o the problems of metallic conduction and the properties of semiconductors has given us a much clearer insight into the fundamentals of thermionic emission by clean metals and oxide cathodes, respectively. Dr. Reimann’s book, whilst preserving an admirable balance between theory and experiment, has not neglected t o give considerable space t o the pioneer work of Richardson, H. A. Wilson, and others, which did so much to set the subject on its feet. The outlook of the book is entirely fundamental and physical, a n 4 the author has wisely left accounts of the obvious practical applications of his subject to others. The techniques of preparing the various thermionic emitters for accurate physical measurement are dealt with in a very clear way; to the practising physicist as well as to the theoretician and student the book is certain to be as valuable as it is timely. 57 1
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The main items of the book deal with electron emission from clean metals, from contaminated metals, and from oxide cathodes; in addition there are chapters on the emission of ions and modern general theory of electron emission. To the render not so interested in the detailed presentation of the subject there is an introductory general survey of sixty-seven pages, which should be of great value to physical chemists. Perhaps in a later edition Dr. Reimann might even extend and simplify this chapter a little, as many of the conceptions and arguments may be a little difficult for the non-specialist to grasp on a first reading. A section of the work which may be of more special interest t o readers of this journal is concerned with the electron emission from contaminated metals such as cesium on tungsten (W-Th), barium on oxygenated tungsten (W-0-Ba) etc. The book contains considerable information not available elsewhere on this aspect of thermionics; it is well produced and printed, and it possesses the rare virtues of being well-written and indexed. J. T. RANDALL.
Strahlentherapie in Icolloidchemischey Betlachung. By R. E. LIEBEGANG.25.5 x 18.5 cm. 46 pp., being pp. 871 to 914 of the Textbook of Medical Colloid Therapy, by Drs. L. Lichtwitz and R . E. Liesegang and Prof. Dr. Karl Spiro. Dresden: Verlagsbuchhandlung Theodor Steinkopff, 1934. Price: 3.00 RM. This small monograph consists largely of tabulated results of various related publications, dealing with the effects of radiation (light, ultra-violet, x;rays and gamma rays) upon living tissue, considered from the aspect of colloid chemistry. I n a short preliminary note the view is advanced that the evolution of species and the non-survival of prehistoric species may be due to the change of type of the radiation incident on the surface of the earth. The action of radiation of different wavelengths upon purely inorganic colloids is first considered on the basis of tabulated findings of various investigators, and the results are briefly discussed from the aspect of molecular charge and photochemical action. Further tabular data are given in respect to the action of radiation on various proteins, which come into question in physiological processes, the “heat point” theory of Dessauer being introduced. Similarly the effects of radiation upon ferments and their action is discussed, followed by a section on the action upon bacterial cultures. This leads to sections of more direct interest to the practical medical radiologist as to the effects of radiation upon the blood, protozoa, egg and ovarian tissues, and isolated organs. Finally the effectsupon living skin and carcinomatous tissues are tabulated and briefly discussed. The monograph, being largely in tabular form, will be of assistance even t o those not reading German, but the subject matter is of limited interest, being practically addressed to the few medical radiologists carrying on intense radiation treatment of cancer and other diseases, rather than to those interested in the underlying biochemical phenomena. B. J. LEQGETT.
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Das Wasserstofisotop. By R. FRERICHS. Ergebnisse der exakten Naturwissenschaften, Sonderabdruck aus Band XI11 (not sold separately). 23 x 15.5cm.; pp. 258309. Berlin: Julius Springer, 1934. Price: unbound, 28 RM; bound, 29.40 RM. This small monograph gives a good account of the investigations on heavy hydrogen which had been carried out to the first part of 1934. Considerable attention is devoted to the method of separation. The physical properties are next considered, including nuclear properties and disintegration by the D_pucleus. Something is said of the isotope H3. The molecules H D and Dz and the equilibrium between them are dealt with. The rest of the material is mainly concerned with the physical
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and chemical properties of heavy water. The article is illustrated and provided with a bibliography of 186 items, which may perhaps illustrate the active interest in the new isotope shown in such a short period of time. J. R. PARTINGTON.
Gmelins Handbuch der anorganischen Chemie. 8 Auflage. Herausgegeben von der Deutschen Chemischen Gesellschaft. System-Nummer 35: Aluminium, Teil A, Lieferung 2. 26 x 18 cm.; vi 285450 pp. Berlin: Verlag Chemie, 1934. Price: 34 RM. Subscription price: 22.50 R.M. The volume deals with the electrochemical properties of aluminum, with its reactions with non-metals, metals, compounds of non-metals (including corrosion) and metals, solutions, and organic compounds; with the hydrolysis of aluminum salts; and with the qualitative and quantitative analysis of aluminum, and the methods of testing the corrodibility of the metal. The subjects are treated very thoroughly and with references to the literature. The volume maintains the high standard of the work in general and includes a good deal of information of physicochemical interest. J. R. PARTINQTON.
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Einfiihrung i n die Lehre von den Kolloiden. By H. BECHHOLD.23.5 x 16 cm.; 160 pp. Leipsig: Steinkopff, 1934. Price: 10 RM. This small volume contains a series of chapters dealing with various properties of colloid systems and written by different authors; the introductory chapter was written by Dr. Bechhold. Dr. Hock deals with the methods by which colloid particles can be identified in properties with macro-molecules as well as their assemblage in sols and gels. Two chapters were contributed by Dr. Heymann on interfaces and the electrical properties of colloid systems. The preparation and purification of colloids are discussed by Drs. Schware and Erbe, whilst two chapters on the optical properties and x-ray examination of colloid systems were written by Drs. Hauser and Brill. Whilst the book scarcely attains the ideal aimed at by the editor, vie., a complete survey of the present position of colloid chemistry and physics, it is nevertheless very readable and would serve as a general introduction to those who wish t o take up the subject. The chapters on the optical properties and x-ray examination are especially to be commended. E. K. RIDEAL. The Atom. By J. TUTIN. 14 x 22 cm.; 103 pp. London: Longmans, Green and Co., 1934. Price: 6s. The conception of the Rutherford-Bohr atom has paved the way for advances in many branches of science; it has also satisfied one of the tests of a useful theory in its ability t o predict new facts. Therefore some surprise is occasioned when the claim is made that an “inverted” atom, with the electrons in the nucleus and the massive particles circulating in orbits outside, would serve equally well to explain the facts. Dr. Tutin makes such a claim in his book, and goes further in stating that his “alternative” atom explains in a simple way many important phenomena of physics and chemistry which are so familiar that they are accepted as though no explanation were necessary. Prominent among these explanations is the distinction between metal and non-metal, a distinction which, though forming the basis of the study of chemistry, finds no expression in the orthodox picture of the atom. I n Dr. Tutin’s theory, however, atoms of metals are provided with free electrons external t o the nucleus.
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The most radical change which the new theory suggests is in the mechanism of valency. This, in the orthodox view, is a concern of electrons, and therefore should be able to be correlated with spectral emission. To provide a similar mechanism for both valency and spectralaemission implies that those atoms which are chemically most active should be most easily excited optically. That this is not true is wellknown. Oxygen, one of the most active chemically, yields a spectrum only with difficulty; the inert gases are notably easy t o excite spectrally and yet are assumed, because of their chemical inertness, t o have their electrons in very rigid configurations. It appears t o the reviewer that on these grounds any alternative atom merits close examination. Let us see how Dr. Tutin finds an alternative. He notes that it is unsatisfactory to have (1) an electronic mechanism for both valency and spectral emission, (2) no distinction between metal and non-metal. He overcomes the latter by allotting free electrons to metals, Le., by furnishing a mechanism associated with ease of spectral emission. But do the properties of elements warrant a close parallelism between ease of spectral emission and metallic nature? Dr. Tutin’s argument seems to suggest so, and yet his scheme does not show i t (radon with twenty-two free electrons should surely be a metal). Has he not removed one difficulty only to raise another? The “inverted” atom of Dr. Tutin is not so simple t o grasp as the name suggests. It is not merely a “mirror image” of the Rutherford-Bohr one. The nrcleus consists of electrons only, and their number is given by the atomic number of the element; but around the nucleus we may have isolated protons or electrons, or combinations of these in one or more of six possible groupings. (The stability of the nucleus is not discussed, but “since extranuclear electrons are repelled by the nucleus, they can only be tied t o the atom by attaching themselves to groups of protons.”) At the outset, therefore, the author has made ad hoe assumptions flexible enough one would imagine t o allow him to “explain” anything. It could be justified only if i t gave a neat and consistent picture of the elements of the Periodic Table. But a glance a t the structures suggested reveals no such consistency. There is little resemblance between the structures of related elements, e.@;.,the halogens, nor even between the structures of the inert gases. The weakest point in Dr. Tutin’s essay is in his treatment of isotopes. This is all but shelved by his assumption that single protons may be used as constructional units and placed near the nucleus where they play no part in atomic union. The difference between an atom and its isotope, however, does not concern protons only, but an equivalent number of electrons. What happens to these? Dr. Tutin does not say, but in the solitary example discussed by Lie and Li7, i t appears that Li7 has a free electron whilst Lie has not. According to his theory the former should conduct electricity, whereas the latter should not. Dr. Tutin does not make the prediction, although there are grounds for believing that i t may soon be possible to test it experimentally. The impression given by the book is that i t is immature in that it deals superficially with a vast number of properties without adequate discussion of any one of them; and that the space devoted to justifying the Law of Causation would have been better used to meet the objections likely to be raised by the champions of the Rutherford-Bohr atom. It is difficult to say for whom the book was written. The general student is not competent to weigh the evidence produced; the specialist would not be satisfied with vague claims of what the theory involves, but would need a much more detailed discussion of each point raised. JOHN A. CRANSTON.
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Journal of the Institute of Metals. Volume LV (Proceedings). 304 pp. 17 plates. Edited by G. Shaw Scott, M.Sc., F.C.I.S. London: The Institute of Metals, 36 Victoria Street, Westminster, S.W.l. Price: JXlls.6d. plus 6d. postage inland, 9d. postage overseas. The latest volume issued by the Institute of Metals is essentially a record of the papers presented at the Manchester Autumn Meeting and of the discussions on these papers. A special contribution is the Autumn Lecture, which deals with the work of Walter Rosenhain, a distinguished past president of the Institute, who died in 1934. A complete record of his published work forms a valuable appendix to the lecture; the list covers five closely printed pages. A great part of the present volume consists of a very practical series of communications, together with a general discussion, on the improvement of white bearing metals-a subject of much interest t o engineers a t the present time.
and M. W. ZEMANResonance Radiation and Excited Atoms. By A. C. G. MITCHELL SKY. 338 pp., 84 figures, and 56 tables. New York: The Macmillan Co., 1934. The book is an exhaustive treatise on this special topic in molecular physics. I n Chapter I such parts of modern spectroscopy are introduced as are needed in the further development of the subject. The sources of resonance radiation, the resonance lamps, are described and hyperfine structure of line spectra and resonance radiation are covered. Physical and chemical effects connected with resonance radiation are dealt with in Chapter 11. Some of the topics included are: stepwise radiations, sensitized fluorescence, interaction of excited atoms with molecules and attendant chemical effects. The principle of microscopic reversibility or of detailed balancing or complete equilibrium is fully discussed in a most satisfactory manner. I n Chapter I11 the authors cover the topic of absorption of light and the determination of the life time of the resonance state. Some of the sections are: the absorption coefficient of a gas, the emission and diffusion of resonance radiation, absorption within a resonance line as compared with the absorption of its edges, the magneto rotation and dispersion of the edges. Chapter IV contains a n account of the collision processes involving excited atoms, the broadening of spectral lines, and the quenching of resonance radiation, while Chapter V concerns the phenomenon of polarization of this type of radiation. An appendix contains several pertinent derivations of formulas and tables of functions. Each chapter ends with a complete bibliography of the subject matter dealt with, giving in alphabetical order references to the original literature. The style is simple and the story is unfolded in a direct and forceful manner. All students of modern atomic, molecular, and chemical physics will welcome this volume, as it brings together the complete literature of a n interesting and important development of modern spectroscopy. GEORGEGLOCKLER. T h e Sub-Atom. By WILLIAMM. VENABLE. 148 pp.; 11 figures. Baltimore: The Williams and Wilkins Co., 1933. The author tries to establish a different theory of matter than is held by modern chemists and physicists. He does not like the Bohr-Rutherford model of the atom with its positive massive center and its planetary electrons. He says: ‘‘Atoms are revealed as composite bodies made u p of aggregations of ions each with a positive charge +e, accompanied with its negative charge -e. These smaller ions each with its electron are designated sub-atoms.” The book is the product of an active mind trying t o change every concept with which it comes in contact. The alpha particle has mass 2 and not 4 and a charge +e and not 2e. The modern concept of light emis-
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sion and absorption by atoms is no good. Hydrogen spectra found as impurity in spectroscopic investigation are not due t o such impurity a t all, but arise from the fact t h a t hydrogen is contained in all other heavier elements as a sub-element. One wonders why the author condescends to use any current concept a t all. He probably could not think of replacements or he would have done so. To anyone even only superficially acquainted with modern chemical physics, the book is very annoying. However, from another point of view, it is interesting reading. It stimulates one’s interest in reviewing the arguments which have led to our modern concepts of atomic and molecular structure. GEORGEGLOCKLER.
Theoretical Physics. Vol. 11. Electromagnetism and Optics. (Maxwell-Lorentz). By W. WILSON. 315 pp.; 78 diagrams. New York: E. P. Dutton and Co., 1933. I n this second volume the author continues his treatment of theoretical physics based on notes from lectures to university students. He covers electrostatics (Chapter I), polarization in dielectric media (Chapters I1 and 111), magnetostatics (IV), electromagnetism (V and VI), thermoelectric currents (VII), Maxwell theory (VIII), and electron theory (IX and X). The very nature of the subject demands the mathematical treatment the author accords it. I n his preface he points out the special form of the electromagnetic field equations in which an unusual notation brings out a four-dimensional appearance suggestive of relativity theory. This material covers 234 pages, leaving only about 80 pages for five chapters on optics. These cover geometric optics (XI), physical optics, interference and diffraction (XII), Huygens’ principle (XIII), propagation of light in crystalline media, polarized light (XIV), and general questions concerning the propagation of light (XV). Some of the chapters have a bibliography appended, where the interested reader can find the best known references concerning the material discussed. This seems particularly fortunate in the latter chapters, for the treatment there is certainly concise and not one word is wasted; This treatise on theoretical physics should appeal particularly to chemists as a reference-set where they can expect to find precise statements concerning the various topics discussed. GEORGEGLOCKLER.
